Damage evolution of fiber-reinforced ceramic-matrix composites under stress-rupture and cyclic loading at elevated temperature in oxidizing atmosphere

Abstract

In this paper, the damage evolution of fiber-reinforced ceramic-matrix composites (CMCs) subjected to stress-rupture and cyclic fatigue loading at elevated temperatures in oxidizing atmospheres has been investigated. The damage parameters of hysteresis dissipated energy, hysteresis modulus, peak strain and hysteresis width have been used to monitor the damage evolution inside of CMCs. The effects of the hold time, stress levels, matrix crack spacing, fiber volume fraction and oxidation temperature on the evolution of damage parameters versus applied cycles have been analyzed. The experimental fatigue hysteresis loops, interface slip lengths, fatigue hysteresis dissipated energy and peak strain of cross-ply SiC/MAS, 2D SiC/SiC and NextelTM 720/Alumina composites subjected to cyclic fatigue and stress-rupture at elevated temperatures have been predicted.